Satinderpal Kaur

Review: the characterization of electrospun nanofibrous liquid filtration membranes

Electrospun nanofibrous membranes (ENMs) are used in a variety of applications, including sensors, tissue engineering, air filtration, energy, and reinforcement in composite materials. Recently, they have gained an interest in the field of liquid filtration. The membranes, surface, bulk, and overall architecture play an important role in the filtration properties and hence the right characterization technique needs to be established, which will pave the way for future developments in the field of filtration. In this article, we have reviewed the recent advances in ENMs for liquid separation application.

OLIGOSACCHARIDE FUNCTIONALIZED NANOFIBROUS MEMBRANE

An attempt was made to incorporate β-Cyclodextrin (β-CD) onto the surface of the nanofiber to target potential applications in organic waste treatment. Phenylcarbomylated and azido phenylcarbomylated β-CD were successfully blended with poly(methyl methacrylate) (PMMA) and electrospun into nanofibrous membrane respectively with an approximate diameter of 900 nm. The presence of this selective agent on the surface of the nanofibers was confirmed by ATR-FTIR and XPS. To determine the functionalized membranes ability to capture small organic molecules, a solution containing phenolphthalein (PHP), a small organic molecule, was used. The results obtained showed that the functionalized nanofibrous membranes were able to effectively capture the PHP molecules. Thus the developed β-CD functionalized nanofibrous membranes may have the potential to capture similar small organic molecules in organic waste.

Potential of Engineered Electrospun Nanofiber Membranes for Nanofiltration Applications

In the area of filtration and separation processes, many variants of fibrous media have been used to improve the quality of water. Among woven and nonwoven filters, nonwoven filters are more commonly used in filtration technology, such as in water treatment, medical filtration processes, and pharmaceutical processes due to their high filtration performance. Nanofibers are the next generation of nonwoven filter media, which offer unique properties, such as a high specific surface area–to-volume ratio, good interconnectivity of pores, and potential to incorporate active chemistry or functionality on a nanoscale. However, the use of nanofibers in water filtration is still at its infancy. Various parameters such as the nature of the polymeric materials, surface architecture, and pore size of the nanofibers influence its separation performance. Currently, as-spun electrospun nanofibrous membranes (ENMs) are applied as microfiltration (MF) membranes. Recently, replacement of the ultrafiltration (UF) middle layer in conventional thin-film composite (TFC) membranes (in three-tier arrangements) by ENMs was used to form thin-film nanocomposite (TFNC) membranes, which provide an improved flux over TFC membranes. Optimization of various parameters such as spinning conditions, TFNC membrane processing, and their influence on the removal of divalent and monovalent ions studied in nanofiltration (NF) applications are concisely reviewed.